At 4 a.m., roiling walls of detritus were racing down all four creeks.
A few hundred feet above the Grokenberger house on Hot Springs Road, Montecito Creek didn't make the east turn it was supposed to at the channel to go under the little bridge. It pushed straight through the neighborhood.
From upstairs, the Grokenbergers' son, 27-year-old Billy, heard a crash below.
He had been videotaping the destruction from a window and continued filming as he walked down the stairs. Blackish mud four feet deep covered the bottom floor. The mud had come through the back and pushed out the front door, jambs and all. Outside, the river roared past, glowing orange under the light of the distant fire.
The home of their next-door neighbors to the north, the Cantins, was gone.
Behind them, their close friends, John McManigal and his son Connor woke up to noise. The only ones home, they stood next to each other as their house twisted, the roof opened up and the floor gave way. They clung to each other underwater, until the current ripped them apart.
Connor, 23, found himself racing downstream.
Other people were caught by the water also -- sucked under the current, bashed by rocks, snagged in giant root balls of trees.
Many were swept into San Ysidro Creek, a little over a mile to the northeast. The mudflow buried homes up to their eaves, packed the insides of some with timber and rocks, obliterated others.
Josie Gower had stacked two rows of sandbags around her home on East Valley Road, in the voluntary evacuation zone. The 69-year-old had an adventurous streak. She was a world traveler who met her ex-husband, a farmer from New Zealand, on a trip to the South Pacific. Having survived the Thomas fire last month made the predictions of this storm seem benign by comparison.